The correct answer is SilicaExplanation:A pigment is a coloured substance that is completely or nearly insoluble in water.SilicaSilica makes up a large portion of the earth's crust, it is widely available. Silica, or silicon dioxide, occurs as crystalline Quartz in its purest form.Although silica is not commonly used as a pigment, it can be found in grounds, primers, and wood fillers. Silica is a mineral that is used in the production of glass, water glass, abrasives, ceramics, and enamelware.Additional InformationChalk Chalk is a sedimentary carbonate rock that is soft, white, and porous. It is a type of limestone made up of the mineral calcite that was formed deep beneath the sea by the compression of microscopic plankton that had settled on the sea floor.Whiting is finely ground and purified chalk that is used as a filler, extender, or pigment in a wide range of materials such as ceramics, putty, cosmetics, crayons, plastics, rubber, paper, paints, and linoleum.Zinc oxideZinc oxide (zinc white) is a paint pigment that is more opaque than lithopone but less opaque than titanium dioxide.White leadWhite lead is a heavy, white substance that is poisonous and insoluble in water. It is widely used as a white pigment and paint base. It is one of the most ancient paint pigments used by humans.